This invention regards a pipe joint lubrication device. More particularly, it regards a pipe joint lubrication device for lubrication of the threads of a pipe socket (socket) and of a pipe nipple (nipple). The lubricant is sprayed on while the nipple is rotated relative to the socket, the rotation taking place about the longitudinal axis of the socket and the nipple. The pipe joint lubrication device is particularly well suited for lubrication of the joints of a pipe string, such as is known from e.g. petroleum exploration and production.
It is customary when joining e.g. threaded drill pipes, to apply a lubricant (dope) on the threads, both in the socket and on the nipple. The purpose of the lubricant application is, in addition to facilitating the coupling and uncoupling of the pipes, to seal the threaded connection between the socket and the nipple when this is exposed to the relatively high fluid pressure encountered during drilling.
Previously it has been customary to apply the lubricant manually by means of e.g. a brush, However, mechanized lubricating apparatuses have been developed, in which the lubricant is sprayed onto the threads via nozzles, e.g. by use of compressed air.
Mechanized lubricating apparatuses according to prior art comprise relatively complicated positioning mechanisms and often represent an obstacle to efficient coupling of pipe lengths, as the lubricating apparatus must be brought up to the coupling location for each lubricating operation.
The object of the invention is to remedy or at least reduce at least one of the disadvantages of prior art.
The object is achieved in accordance with the invention, by the characteristics given in the description below and in the following claims.